Apparatus and method for removing a covering film from a container

ABSTRACT

An apparatus and a method are proposed for removing a covering film from a container. The apparatus has at least one gripping apparatus and a mechanism for producing a predetermined breaking point on a container. After production of the predetermined breaking point, the gripping apparatus grips a gripping face which is delimited by the predetermined breaking point, for removing the covering film from the container, and separates the gripping face during the removal of the covering film from the container.

PRIOR ART

The invention is based on an apparatus and a method for removing a covering film from a container, as generically defined by the preambles to the independent claims.

In German Patent Disclosure DE 10 2004 003 232 A1, a method is described in which the front and rear peripheral regions of the film are first heated (for instance with an infrared radiator). The container next passes beneath a large roller that is provided with suction devices. By means of the suction devices, which are arranged in a plurality of rows radially, the film is wound up onto the roller. The insert film is removed in the same way, by a further roller. By pivoting the entire roller unit next to the conveyor belt, the films are moved across a collection container, where they are set down by contrary rotation of the rollers.

In German Patent Disclosure DE 44 19 475 A1, the covering film is not heated; that is, the film is drawn off at room temperature. The container first moves into an exactly defined position. A gripper mechanism, controlled by a handling system or robot system, grasps a (corner) tab and in the process pulls off the covering film. In order to grasp the small tab more securely, however, it is necessary that the gripper first move into the vicinity of the tab, to the edge of the container. The gripper closes enough that a small gap still remains above and below the edge of the container, and the gripper then moves to laterally behind the tab. As a result, the tab is stretched out straight into the plane of alignment of the edge of the magazine box when the tab has been bent or dogeared off beforehand. Next, the small, protruding corner is grasped with a gripper and pulled off from the container.

In German Patent Disclosure DE 102 52 572 A1, the glued peripheral region of the covering film is heated in this method with a contact heating frame. The heating frame pivots to the side, and a suction plate moves across the covering film in order to pick it up by suction. Next, pivoting causes the film to be set down laterally. The suction devices may also be integrated with the heating frame.

It is the object of the present invention to achieve simple, secure opening of a container that is closed with a covering film. This object is attained by the characteristics of the independent claims.

DISCLOSURE OF THE INVENTION

The apparatus and method of the invention for removing a covering film from a container having the characteristics of the independent claims have the advantage over the prior art that secure removal of the covering film can be done without producing many particles, because the covering film is reliably grasped in one corner of the container. This is because, by suitably making the rated breaking point on the container, a sufficiently large grip surface can be created that the gripping device securely grasps—in comparison to versions where only the tab, formed from the protruding covering film, is grasped. The grip surface could for instance be one complete corner of a rectangular container that is still at least partially joined to the covering film. Thanks to the enlargement of the grip surface, the positioning of the container need not be done completely exactly, since the grip surface provides enough room that it can be securely/grasped. While the covering film is being dogeared and then pulled off, only very few contaminating particles are formed. Thus the apparatus and method for removing a covering film from a container are especially well suited to pharmaceutical applications.

In an expedient refinement, it is provided that the means for creating the rated breaking point orient the rated breaking point perpendicular to the direction in which the covering film is removed. The gripping device can be positioned, with correct orientation, once and for all, and after that it can both sever the grip surface and pull off the covering film in a single course of motion. The covering film can now be pulled off directly in the plane of the adhesive. This can be done with only little expenditure of force.

In an expedient refinement, it is provided that the gripping device, in severing the grip surface from the container, executes a tilting motion. This kind of tilting motion is especially well suited for not damaging the covering film as the grip surface is broken off. Preferably, the tilting motion is effected such that the grip surface is moved in the direction of the side diametrically opposite the rated breaking point. This means that a relative motion of the rated breaking point that is directly covered by the covering film is thus minimized, and hence the risk that the covering film will tear is reduced.

In an expedient refinement, it is provided that heating means are provided for reinforcing the detachment of the covering film from the container and/or for reinforcing the creation of the rated breaking point. As a result, less force has to be exerted on the covering film or the container when the covering film is pulled off or the rated breaking point is made. The double utilization of the heating means for detaching the covering film and for reinforcing the creation of the rated breaking point by heating the punching means and/or the container, for example, is especially advantageous, as it makes the apparatus less expensive. By means of contact heat, the covering film is heated only in the glued peripheral region of the container, so that an insert film, which is present for protecting the contents of the container, is no longer joined to the covering film. This is the case particularly if the heating means is embodied as a heating frame that is oriented to the geometry of the lid of the container.

In an expedient refinement, it is provided that at least one conveyor means is provided, which feeds the container from the work area of the means for creating the rated breaking point into the work area of the gripping device. As a result, the basic functions of creating the rated breaking point and pulling off the covering film can be performed on a single machine.

In an expedient refinement, it is provided that the means for creating the rated breaking point include at least one moving means for moving the knife and/or the container relative to one another, preferably using a stop. As a result, a defined force, dimensioned such that the covering film that covers the other side of the edge of the container is not affected, can be exerted on the container. Hence the rated breaking point can be formed in such a way that on the one hand the covering film is not severed, yet on the other hand, it is reliably assured that the grip surface will be dogeared.

In an expedient refinement, it is provided that the heating means serve to heat the knife. As a result, less force is required in the punching operation for creating the rated breaking point.

Further expedient refinements will become apparent from further dependent claims and from the description.

DRAWINGS

One exemplary embodiment of the apparatus of the invention is shown in the drawing and will be described in further detail below.

Shown are:

FIG. 1, a detail of a perspective view of a container with a rated breaking point;

FIG. 2, a container with a dogeared grip surface;

FIG. 3, an apparatus for removing a covering film from a container;

FIG. 4, a cross section through the means for creating a rated breaking point in interaction with the container;

FIG. 5, a view of a corner of the container from below;

FIG. 6, a corner of the film being lifted by a vacuum suction device; and

FIG. 7, a container with a lateral recess.

The surface of a container 10, surrounded by a container edge 16, is closed with a covering film 12. The container 10 is for instance in rectangular form. A rated breaking point 14 is located on the underside of the outward-protruding edge 16 of the container. The rated breaking point 14 is disposed such that one corner of the container edge 16 can be severed from the container 10. The covering film 12 covers the corner region of the container edge 16. The severable corner region forms a grip surface 18, which is grasped by a gripping device for severing the grip surface 18 from the container 10 and then pulling off the covering film 12. In FIG. 2, the grip surface 18, dogeared upward, can be seen; the grip surface 18 and container 10 are still joined together at least by the undamaged covering film 12.

In FIG. 3, an apparatus for removing the covering film 12 from the container 10 is shown. It comprises a table 24, on which means 28 for creating the rated breaking point 14, a heating means 30 embodied as a heating frame, a manipulator 34 that moves a gripper 32, a waste bin 38, and a conveyor means 26 embodied as a conveyor belt that conveys the container 10 to the various processing stations are disposed. A pressing tappet 36 reinforces the deposition of the covering films 12 that have been removed in the waste bin 38. An insert film 40 that is also to be removed is also located in the container 10.

In FIG. 4, the means 28 for creating the rated breaking point 14 are shown in further detail, as one possible embodiment. A knife 44 can be displaced vertically by moving means 45. The motion is limited toward the top by a stop 42, so that the knife 44 can provide the container edge 16, located between the stop 42 and the tip of the knife, with a notch of defined depth, which is the rated breaking point 14. The geometry of the arrangement is selected here such that when the rated breaking point 14 is made, on the one hand the covering film 16 that covers the container edge 16 is not damaged, but on the other, the rated breaking point 14 in the container edge 16 is deep enough to assure that the grip surface 18 will be reliably broken off from the container 10. In FIG. 5, the location of the rated breaking point 14 on the container edge 16 is shown once again. The corner thus created forms the grip surface 18.

In FIG. 6, a vacuum suction device 20 is provided, which lifts the covering film 12 at one corner of the container 10 from the container edge 16 in order to pull it off the container 10 after that.

In the exemplary embodiment of FIG. 7, on at least one corner of the container 10 or container edge 16, a recess 22 is provided, which is preferably oriented in the diagonal direction of the container 10.

The covering film 12 that is intended to close the container 10 is provided with an adhesive layer on the underside of the covering film 12. This layer is sealed onto the container 10 by the manufacturer; that is, a heated frame moves onto the covering film 12 and thus with pressure and a defined temperature seals the film 12 onto the container. This method is used for instance for producing boxes for syringe nests. The presterilized syringes are inserted as a nest into the so-called tub, as an example of a container 10. Next, an open-diffusion film (insert film 40) is then placed on the bodies of the syringes. At the end of the process, with an open-diffusion covering film 12, the container 10 is closed. This film is then packaged in a film bag under sterile conditions and supplied to the pharmaceutical manufacturer. As a result, the pharmacist is relieved of having to perform the complicated processes of cleaning and sterilization. Moreover, the complicated processes of assembling the components of the syringe (such as glass body, needle, needle guard, etc.) and siliconizing them, which requires a great deal of knowhow, are shifted from the pharmacist to the vendor. The pharmacist furthermore has substantially greater flexibility in processing different sizes of syringes; that is, the reset times for changing the filling machines to different sizes are faster.

Before the syringe bodies in the syringe nest are filled, the covering film 12 must be removed. This operation is currently performed either in the cold state of the film 12, or else the covering film 12 is first heated in order to minimize the force involved in pulling off the film 12. With the apparatus shown in FIG. 3, the covering film 12 can be removed especially reliably, as will be described in further detail below.

Before the covering film 12 is grasped and pulled off, on the underside of the container corner or edge 16 a rated breaking point 14 is created, for instance by the knife 44. The location of the rated breaking point 14 is perpendicular to the diagonal direction in which the covering film 12 is pulled off. This process can be done at room temperature, or with heating of the container edge 16 and/or of the knife 44.

In the next process step, the gripping device, comprising the gripper 32 and the manipulator 34, grasps the grip surface 18 created by the rated breaking point 14, or in other words grasps the complete corner of the container edge 16 with the covering film 12. This grip surface 18 is large enough that it can be securely held by the gripper 32. For that purpose, the container 10 is roughly pre-positioned beforehand. By means of a slight tilting motion, the grip surface 18 is broken off by the gripping device 32, 34, so that the gripping device securely holds the broken-off grip surface 18 along with the undamaged covering film 12. The tilting motion is oriented such that the outermost corner of the grip surface 18 is broken off upward, or in other words in the direction toward the covering film 12. As a result, damage to the covering film 12, particularly in the region of the rated breaking point 14, can be avoided. The material comprising the container edge 16 shown be severed to such an extent, in the making of the rated breaking point 16 [sic; German page 7, line 15; should be rated breaking point 14, that on the one hand, the covering film 12 is not severed as well, and on the other, it is securely assured that the grip surface 18 will be dogeared. This depends on the material and thickness of the container edge 16. Next, the covering film 12 is pulled off by the gripping device 32, 34. A prior heating of the edge of the film can reinforce the detachment of the covering film 12 from the container edge 16.

FIG. 3 shows one possible sequence in which the covering film 12 is pulled off by creating the rated breaking point 14. This involves intermittent conveyance, with four work steps. In step 1, the container 10 is roughly prealigned. Next, the opened knife 44 of the rated breaking point-creating means 28 moves to the corner of the container 10. Via a drive mechanism as a component of the moving means 45, the knife 44 is moved upward into the plastic comprising the container edge 16, as shown in FIG. 4, and thus creates the rated breaking point 14. The location of the rated breaking point 14 should ideally be perpendicular to the diagonal of the container, but may also deviate somewhat from that. A stop 42 connected to the knife 44 prevents the knife 44 from severing the covering film 12 as well. The stop 42 should be adjusted such that the plastic container edge 16 is severed as extensively as possible, yet without damaging the covering film 12. The creation of the rated breaking point 14 can be done in the cold state, but if so, a relatively strong force is required. The force can be minimized and the creation of contaminating particles can be reduced by heating the knife 44. As the heating means for heating the knife 44, a heating cartridge or other heating elements may be employed.

In step 2, the container 10 is moved to below the heating station or heating means 30 (such as contact heating or a heating frame) and positioned as in step 1. What is important here is that only the glued peripheral region of the covering film 12 or container edge 16 is heated, and that the surroundings are not severely heated, so as to affect the laminar air flow as little as possible, to prevent interfering particles from getting inside the container. Contact heating is especially suitable for this purpose. since the heat is imported in a targeted way into the material to be heated, and the heat development in the surroundings is minimal: This is advantageous especially in comparison to infrared radiators.

In step 3, the covering film 12 is then pulled off with a gripper 32. The gripper 32 moves to the corner of the container and grasps the grip surface 18 located ahead of the rated breaking point 14. Exact positioning of the container 10 is not required here, either. The gripper 32 should be movable in such a way that as it moves upward it can easily dogear the grasped corner or grip surface 18 and then breaks it off. This can be done via a controlled rotary motion. However, it is also conceivable for the gripper 32 to be rotatably supported only horizontally and to be kept in this basic position via a spring. Thus the gripper 32 can pivot along with the covering film 12 in the process of removing the covering film and reinforces the process of breaking it off. A drive mechanism can furthermore be dispensed with. When the gripper 32 now moves upward and in the direction of the center of the container, the grip surface 18 breaks off, and the gripper 32, with the grip surface 18 and the covering film 12, rotates counter to the spring force.

For pulling the covering film 12 off further, the gripper 32 can move parallel to the top of the container. After the covering film 12 has been pulled off, the gripper 32 is restored to its basic position via the spring force. Polystyrene (PS) is in particular highly suitable for the container 10 or the container edge 16.

The covering film 12 can be pulled off along various paths of motion; in terms of the expenditure of force, the simplest is a diagonal motion of the gripper 32 above the container 10. Other motions are also possible, such as a kind of circular motion. That has the advantage that the pivoting range of the manipulator 34 is made smaller.

After being pulled off, the covering film 12 is deposited in the waste bin 38. The gripper 32 returns to its outset position.

In step 4, the insert film 40 can be removed, but that can also be done later instead.

As the heating means 30 for reinforcing the detachment of the covering film 12, a contact heating frame is especially suitable; it is more suitable than short-wave infrared radiators. This is because infrared radiators are very bright and hence unpleasant to the eye. Furthermore, infrared radiators develop a great deal of heat and thus interfere with the laminar air flow, which could cause an unwanted importation of particles into the interior of the container. Infrared radiators furthermore have a high connected electrical load and thus high ongoing costs.

Alternative embodiments are also possible. For instance, the knife 44 can be integrated with the heating station or the heating means 30. In the first step, the container edge 16 is heated from above by a contact heating frame as a heating means 30. For counterpressure, a receiving frame is needed, into which the container 10 is inserted. The rated breaking point 14 is created simultaneously with the heating. For that purpose, the knife 44 is integrated with one corner of the receiving frame and should be heated. The advantage of this arrangement is that the separate station for creating the rated breaking point can be dispensed with.

In a further alternative exemplary embodiment, the gripping device 32, 34 and the means 28 for creating the rated breaking point can be combined, by means of a special gripper 32. In the first step, the container edge 16 is heated with the heating frame as a preferred heating means 30. In the second step, the grip surface 18 is grasped by a combination gripper comprising the knife 44 and the gripper 32. The gripping mechanism clamps the grip surface 18. The knife 44 creates the rated breaking point 14. Next, the grip surface 18 is dogeared in order to pull the covering film 12 off.

This method can also be employed in processes in which the covering film 12 is to be pulled off together with the insert film 40. For that purpose, the heating frame can for instance be embodied such that besides the container edge region, the middle region of the container 10 is heated as well.

The covering film 12 can also be pulled off by means of a vacuum suction device 20, as shown in FIG. 6. To that end, the vacuum suction device 20 lifts up the film 12 in the corner of the container 10. For safe function, however, it is necessary for the covering film 12 to be heated in this corner region, so as to reduce the force for the vacuum suction device 20. Next, the raised corner of the film can be grasped by a mechanical gripper 32 and pulled off. The advantage of this method is that the container 10 is unchanged in its shape. The method according to the invention for pulling off a covering film 12 from a container 10 is distinguished by the following steps:

-   -   heating at least part of the covering film 12 and/or of the         container edge 16;     -   lifting the covering film 12 in the vicinity of the heated part         of the covering film 12 by means of a vacuum suction device 20;     -   grasping the lifted part of the covering film 12 by means of a         gripper 32; and     -   pulling the covering film 12 off from the container 10 by means         of the gripper 32.

In the first step, the tub edge is heated with a heating frame as the heating means 30. In the second step, the container corner is lifted up by the vacuum suction device 20 far enough that the gripping device 32, 34 can hold the corner. The gripper 32 and vacuum suction device 20 can either be a unit or they can work separately. If they are separate, the vacuum suction device 20 has to be vented and pivoted away once the covering film 12 is securely held by the gripper 32. Next, the covering film 12 is pulled off as described above.

As a further alternative exemplary embodiment, the corner of the container can be altered in such a way that defined grasping of the covering film 12 can be done securely and without requiring additional provisions. For that purpose, a recess 22 is created in the corner region of the container 10, so that the horizontal location of the covering film 12 is fixed, yet the covering film 12 can be securely grasped by the gripping device 32, 34. This recess 22 must already be made in the production of the containers 10. Thanks to the recess 22, the covering film 12 can be securely grasped. The location of the film tab that could be dogeared is not relevant to its being grasped, since the remaining container edge 16 keeps the covering film 12 in a defined position in the region of the recess 22. Only one gripping device 32, 34 is required. The covering film 12 can be pulled off either cold or warm, depending on what the customer wants. The method according to the invention for pulling a covering film 12 off from a container 10, whose container edge 16 has at least one recess 22 covered by the covering film 12, is distinguished by the following steps:

-   -   heating at least part of the covering film 12 and/or the         container edge 16;     -   grasping the part of the covering film 12 located above the         recess 22 by means of a gripper 32; and     -   pulling the covering film 12 off from the container 10 by means         of the gripper 32.

Heating the covering film 12 and/or the container edge 16 is preferably done using a heating frame. In a further step, the corner of the container is grasped with the gripper 32 in the region of the recess 22. The gripping device 32, 34 clamps the covering film 12 in the region of the recess 22 and pulls it securely off, as already described above. 

1-12. (canceled)
 13. An apparatus for removing a covering film from a container, comprising: at least one gripping device; and means for producing a predetermined breaking point on the container, wherein the gripping device, after producing the predetermined breaking point, grasps a grip tab defined by the predetermined breaking point and separates the grip tab from the container in the course of removing the covering film.
 14. The apparatus according to claim 13, wherein the means for creating the predetermined breaking point disposes the predetermined breaking point essentially perpendicular to the direction in which the covering film is removed by the gripping device.
 15. The apparatus according to claim 13, further comprising heating means for facilitating easier detachment of the covering film from the container and/or for facilitating easier production of the predetermined breaking point.
 16. The apparatus according to claim 14, further comprising heating means for facilitating easier detachment of the covering film from the container and/or for facilitating easier production of the predetermined breaking point.
 17. The apparatus according to claim 13, wherein the gripping device severs the grip tab from the container by a tilting motion.
 18. The apparatus according to claim 14, wherein the gripping device severs the grip tab from the container by a tilting motion.
 19. The apparatus according to claim 15, wherein the gripping device severs the grip tab from the container by a tilting motion.
 20. The apparatus according to claim 13, further comprising at least one conveyor means which feeds the container from a work area of the means for creating the predetermined breaking point into a work area of the gripping device.
 21. The apparatus according to claim 14, further comprising at least one conveyor means which feeds the container from a work area of the means for creating the predetermined breaking point into a work area of the gripping device.
 22. The apparatus according to claim 15, further comprising at least one conveyor means which feeds the container from a work area of the means for creating the predetermined breaking point into a work area of the gripping device.
 23. The apparatus according to claim 16, further comprising at least one conveyor means which feeds the container from a work area of the means for creating the predetermined breaking point into a work area of the gripping device.
 24. The apparatus according to claim 13, wherein the means for creating the predetermined breaking point include at least one knife.
 25. The apparatus according to claim 14, wherein the means for creating the predetermined breaking point include at least one knife.
 26. The apparatus according to claim 23, wherein the means for creating the predetermined breaking point include at least one knife.
 27. The apparatus according to claim 24, wherein the means for creating the predetermined breaking point are a component of the gripping device, and in particular, the knife is integrated with the gripper.
 28. The apparatus according to claim 24, wherein the means for creating the predetermined breaking point include at least one moving means for moving the knife and/or the container relative to one another.
 29. The apparatus according to claim 15, wherein the heating means and the means for creating the predetermined breaking point are integrated in a single device.
 30. The apparatus according to claim 24, wherein the heating means serve to heat the knife and/or the container edge.
 31. A method for removing a covering film from a container, comprising the steps of: producing a predetermined breaking point on the container; gripping a grip surface defined by the predetermined breaking point by a gripping device: separating the grip surface from the container; and removing the covering film joined to the grip surface, from the container.
 32. The method as defined by claim 31, wherein the grip surface is separated from the container by tilting the gripping device relative to the surface of the container. 